What Eye Color May Reveal About The Brain

Opinions about eye color have varied over time and culture, with light eyes favored among some cultures and dark among others. To demonstrate this, a recent survey done by Impulse Research in Los Angeles of over 1,000 women found that different eye colors were associated with different personality traits. 34% considered brown eyed people intelligent, kind, and trustworthy while only 7% rated blue eyed people as intelligent but felt they were kind and sweet overall. Another study from Charles University in the Czech Republic found that brown-eyed faces were deemed more trustworthy than blue-eyed ones. But it turns out that while personal tastes and fashions change, there is more that eye color can tell us than simple cosmetic preference.

Pain Tolerance

A 2014 study from the University of Pittsburgh linked eye color to pain tolerance. Researchers compared pain tolerance during childbirth and results showed women with light eyes tolerated pain better during childbirth and reported less post-partum depression, while those with dark-colored eyes responded to pain medication faster, suggesting they may be more sensitive to pain. While this was just a pilot study and more research is needed, it most likely indicates a genetic link.

Athleticism

Researchers have connected eye color to light sensitivity, with people with lighter eyes showing more sensitivity to light – which may also impact physical attributes like reaction time. Studies have revealed that darker eyes may have an advantage in sports, due to faster reaction time as a result of the reduced sensitivity to light. Specifically, a study done at the University of Louisville, KY found that men with dark eyes performed better than those with light eyes in a test study hitting racquetballs. While this does bode well for sports like boxing or baseball, researchers also noted that light eyed people do better in sports that are self-paced like golf or bowling. Studies are ongoing and reports have been mixed, researchers from Fort Hays State University, KS found no correlation between eye color and coordinated target-hitting when studying school-age children.

Alcohol Tolerance

Researchers at Georgia State University found that individuals with light eyes consumed significantly more alcohol than individuals with dark eyes when reviewing data in archival studies. This may indicate that the higher sensitivity to alcohol in dark-eyed individuals impacts their drinking behavior, preventing them from drinking large quantities and developing physical dependence. A new study, from the University of Vermont has connected eye color with alcohol dependence. Researchers found that European Americans with light-colored eyes (green, grey, etc.) had an increased incidence of alcohol dependency than the dark eyed, and the strongest association was among the blue eyed. Their ultimate conclusion being that people with blue eyes may have a greater risk of becoming alcohol dependent.

We now know that eye color is determined by 12 or 13 genes, not the two or three that were originally suspected, and these genes are working in the body in different ways – affecting the brain and overall health in many ways that have yet to be determined. But this research studying identifiable features like eye color with other characteristics like pain tolerance, additive behaviors and other health risks, could greatly enhance clinical care and treatment effectiveness for patients.

To read more about what the eyes can reveal about health, visit PsychCentral.com.